Vehicular image-display system

ABSTRACT

A vehicular image-display system includes an image capturing device, a control device, and an image display device. The image capturing device includes an imaging element configured to capture an image of surroundings of a vehicle, and an image acquirer configured to acquire, based on the captured image captured by the imaging element, an image that is smaller in area than the captured image. The control device includes an image generator configured to generate an image that is smaller in area than the acquired image based on the acquired image acquired by the image acquirer. The image display device is configured to display the image to be displayed generated by the image generator. The acquired image is transmitted from the image capturing device to the control device.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application a continuation Application of U.S. applicationSer. No. 15/486,332, filed Apr. 13, 2017, which is a continuationapplication of International Application No. PCT/JP2015/079377, filedOct. 16, 2015, which claims priority to Japanese Patent Application No.2014-212828, filed Oct. 17, 2014. The contents of these applications areincorporated herein by reference in their entirety.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a vehicular image-display system.

2. Description of the Related Art

Vehicle-mounted cameras are increasingly widespread with widespread ofdrive recorders and around-vehicle monitoring cameras.

Meanwhile, although electronic mirrors that differ from side-viewmirrors and rear-view mirrors are being developed, due to high technicalobstacles to be overcome in terms of safety, reliability, andperformance, electronic mirrors have not gained widespread use yet.

What is required of an electronic mirror is to continue supplying imagesaround a vehicle stably. To achieve this, a system including from acamera to a display is required to perform processing at a highresolution (high pixel density), high contrast, high frame rate, andhigh speed.

A technique that, even though a captured image is used, enables morequick and intuitive awareness of an object to be noticed in thesurroundings of own vehicle is known from, for example, Japanese PatentNo. 4941760.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, a vehicularimage-display system includes an image capturing device, a controldevice, and an image display device. The image capturing device includesan imaging element configured to capture an image of surroundings of avehicle, and an image acquirer configured to acquire, based on thecaptured image captured by the imaging element, an image that is smallerin area than the captured image. The control device includes an imagegenerator configured to generate an image that is smaller in area thanthe acquired image based on the acquired image acquired by the imageacquirer. The image display device is configured to display the image tobe displayed generated by the image generator. The acquired image istransmitted from the image capturing device to the control device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an overall architecture diagram of a vehicular image-displaysystem according to an embodiment;

FIG. 2 is a system architecture diagram of the vehicular image-displaysystem according to the embodiment;

FIG. 3 is a system architecture diagram of a vehicular image-displaysystem as a reference comparative example for the vehicularimage-display system according to the embodiment;

FIG. 4 is a diagram illustrating areas of images used in the vehicularimage-display system according to the embodiment;

FIG. 5 is a diagram illustrating a captured-image-and-mirrorrelationship in the vehicular image-display system according to theembodiment;

FIG. 6 is a diagram describing an example of an image position and areathat are responsive to motion of a driver in the vehicular image-displaysystem according to the embodiment;

FIG. 7 is a diagram describing the example of the image position andarea that are responsive to the motion of the driver in the vehicularimage-display system according to the embodiment;

FIG. 8 is a diagram describing another example of an image position andarea that are responsive to motion of the driver in the vehicularimage-display system according to the embodiment;

FIG. 9 is a diagram describing the other example of the image positionand area that are responsive to the motion of the driver in thevehicular image-display system according to the embodiment;

FIG. 10 is a diagram describing still another example of an imageposition and area that are responsive to motion of the driver in thevehicular image-display system according to the embodiment; and

FIG. 11 is a diagram describing the still other example of the imageposition and area that are responsive to the motion of the driver in thevehicular image-display system according to the embodiment.

The accompanying drawings are intended to depict exemplary embodimentsof the present invention and should not be interpreted to limit thescope thereof. Identical or similar reference numerals designateidentical or similar components throughout the various drawings.

DESCRIPTION OF THE EMBODIMENTS

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the presentinvention.

As used herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise.

In describing preferred embodiments illustrated in the drawings,specific terminology may be employed for the sake of clarity. However,the disclosure of this patent specification is not intended to belimited to the specific terminology so selected, and it is to beunderstood that each specific element includes all technical equivalentsthat have the same function, operate in a similar manner, and achieve asimilar result.

An embodiment of the present invention will be described in detail belowwith reference to the drawings.

FIG. 1 is an overall architecture diagram of a vehicular image-displaysystem 7 according to an embodiment of the present invention. Thevehicular image-display system 7 is installed in a vehicle 101. Thevehicular image-display system 7 includes an image capturing device 3that captures an image of surroundings of the own vehicle and acquiresan image of a necessary area from the thus-captured image, a controldevice 5 to which the acquired image acquired by the image capturingdevice 3 is to be transmitted from the image capturing device 3 via anacquired-image transmission part 9, and an image display device 6attached to the vehicle 101 to display a display image generated by thecontrol device 5.

An in-vehicle camera 11 is attached to inside of the vehicle 101 andcontinuously captures an image of the face of a driver 10. The imagecapturing device 3 analyzes information about line-of-sight position ofthe driver 10 based on image data captured by the in-vehicle camera 11and acquires, from the captured image, an image that is smaller in areathan the captured image based on a result of the analysis.

FIG. 2 is a system architecture diagram of the vehicular image-displaysystem 7 of the present embodiment.

The image capturing device 3 includes an imaging element 1 that capturesan image of the surroundings of the own vehicle, an image calculator 8that calculates an image of a necessary area from the captured imagecaptured by the imaging element 1, and an image acquirer 2 that acquiresan image of the area calculated by the image calculator 8.

The image calculator 8 analyzes information about line-of-sight positionof the driver 10 from image data captured by the in-vehicle camera 11,calculates position and area of a required image based on a result ofthe analysis, and transmits information about the position and area tothe imaging element 1 and the image acquirer 2.

The imaging element 1 captures a rear-view image of the vehicle andtransmits thus-captured image data to the image acquirer 2.

The imaging element 1 captures an image of only a partial image regionof an entire capturable image region based on the information about therequired image position and area received from the image calculator 8and transmits the image to the image acquirer 2. It is preferable thatthe partial image region to be captured by the imaging element 1 coversacross the entire capturable image region in the horizontal directionbut covers only a partial image region of the entire capturable imageregion in the vertical direction.

The image acquirer 2 performs trimming on the captured image receivedfrom the imaging element 1 in accordance with the information about theposition and area of the required acquired image received from the imagecalculator 8, thereby acquiring an image that is smaller in area thanthe captured image. Hence, only the image of the required position andarea is transmitted via the acquired-image transmission part 9 to thecontrol device 5. At this time, the “information about the position andarea” calculated by the image calculator 8 is transmitted via theacquired-image transmission part 9 to the control device 5 together withthe image.

The control device 5 includes an image generator 4 that generates, basedon the acquired image transmitted from the image capturing device 3, adisplay image to be displayed on the image display device 6 inaccordance with the information about the required position and area ofthe acquired image received from the image calculator 8.

In the vehicular image-display system 7 according to the presentembodiment, because only the acquired image, which is a part of theentire area of the captured image captured by the image capturing device3, of the required position and area, which are received from the imagecalculator 8, is transmitted to the control device 5, volume of imagedata to be transmitted can be reduced. Accordingly, image processingload can be reduced, and the surroundings of the own vehicle can bedisplayed quickly.

FIG. 3 is a system architecture diagram of a vehicular image-displaysystem 27 as a reference comparative example for describing an advantageof the present embodiment having the configuration illustrated in FIG.2.

In the vehicular image-display system 27, an image capturing device 23includes an imaging element 21 that captures surroundings of ownvehicle. Image data representing a captured image captured by the imagecapturing device 23 of an entire capturable image area is transmittedvia an image transmission part 12 to a control device 25.

The control device 25 includes an image calculator 28 and an imagegenerator 24. The image calculator 28 analyzes information aboutline-of-sight position of the driver 10 from image data captured by thein-vehicle camera 11, calculates a required image position and areabased on a result of the analysis, and transmits the position and areato the image generator 24.

The image generator 24 generates, based on the image data of the entirearea transmitted from the image capturing device 23, an image to bedisplayed on the image display device 6 using information about therequired position and area calculated by the image calculator 28.

In the reference comparative example illustrated in FIG. 3, imagetrimming or, more specifically, processing of acquiring the image thatis smaller in area than the captured image, is performed by the imagegenerator 24 on the side of the control device 25. Accordingly, theimage data captured by the imaging element 21, inclusive of image datathat is not to be used for display on the image display device 6, is tobe transmitted using the image transmission part 12 from the imagecapturing device 23 to the control device 25.

By contrast, in the present embodiment, processing of acquiring an imagethat is smaller in area than a captured image is performed by the imageacquirer 2 on the side of the image capturing device 3, by which imagedata representing the acquired image of only a position and arearequired by the image generator 4 is obtained. Accordingly, image datatransmitted via the acquired-image transmission part 9 from the imagecapturing device 3 to the control device 5 can be minimized.

A camera used in a general vehicle typically uses, as an image-datatransmission part, a long harness that is several meters long. Becausenoise originating from the image-data transmission part can matterconsiderably, reducing volume of image data transmitted via theimage-data transmission part can lead to considerable effectiveness.Furthermore, in the reference comparative example of FIG. 3, image dataof the entire area captured by the image capturing device 23 istransmitted via the image transmission part 12 to the control device 25.Accordingly, transmission load for an image region that is not to bedisplayed is wasted for no use, which inhibits quick display of thesurroundings of the own vehicle.

FIG. 4 is a diagram illustrating areas of images used in the vehicularimage-display system 7 of the present embodiment.

A captured image 15 is an image captured by the imaging element 1included in the image capturing device 3.

An acquired image 14 is an image of an area calculated by the imagecalculator 8 included in the image capturing device 3 acquired by theimage acquirer 2.

A calculated image 13 is an image position and area to be displayed on adisplay unit calculated by the image calculator 8.

The image generator 4 included in the control device 5 generates, as adisplay image to be displayed on the image display device 6, an imageposition and area corresponding to the calculated image 13 based on theacquired image 14.

The acquired image 14 is an image that is smaller in area than thecaptured image 15 and equal to or larger in area than the calculatedimage 13 calculated by the image calculator 8. The calculated image 13is equal to or smaller in area than the acquired image 14.

Because the acquired image 14 is smaller in area than the captured image15 of the entire area, the acquired image 14 can achieve data volumereduction as compared with the captured image 15. Accordingly,transmission load for transmitting the acquired image 14 to the controldevice 5 can be reduced.

Because the acquired image 14 is equal to or larger in area than thecalculated image 13 that is to be actually displayed, when determiningan appropriate display area of a display image to be displayed on theimage display device 6, the image generator 4 can select the displayarea from an area having a certain extent. As a result, the need forre-capturing an image using the image capturing device 3 can beobviated.

FIG. 5 is a diagram illustrating a captured-image-and-mirrorrelationship. When the captured image 15 captured by the image capturingdevice 3 is used in place of a mirror, as illustrated in FIG. 5, an areaA defined by and with reference to a vertical position of the capturedimage 15 is larger than an area B defined by and with reference to avertical position of an image in the otherwise-used mirror.

FIG. 6 and FIG. 7 are diagrams describing an example of an imageposition and area that are responsive to motion of a driver in thevehicular image-display system 7 of the present embodiment. When thedriver 10 desires to see a subject indicated at a position C in FIG. 6and FIG. 7, the driver 10 typically takes an action D of shiftinghis/her line-of-sight position as does a driver 10 a as an action ofseeing rearward using the mirror. Accordingly, there will arise a desireto see the subject indicated at the position C in FIG. 6 and FIG. 7 bytaking the action D even when the captured image 15 captured by theimage capturing device 3 is used in place of the mirror.

When the captured image 15 captured by the image capturing device 3 isused in place of the mirror, if an image of a position and a large area,such as the area A defined by and with reference to the verticalposition of the image of FIG. 5, is displayed on the image displaydevice 6, unnecessary information having adverse effect on safe drivingcan be given to the driver 10. Accordingly, an image of an area Edefined by and with reference to the position of the image of FIG. 6 ispreferably displayed on the image display device 6 when line of sightextends from the position of the driver 10, while an image of an area Fdefined by and with reference to the position of the image of FIG. 6 ispreferably displayed on the image display device 6 when line of sightextends from the position of the driver 10 a.

When line of sight extends from the position of the driver 10, the imagecalculator 8 analyzes information about the line-of-sight position ofthe driver 10 based on image data captured by the in-vehicle camera 11and calculates, as a required image area, the area E based on a resultof the analysis. The image acquirer 2 acquires the acquired image 14containing the calculated area E from the captured image 15. The imagegenerator 4 generates a display image of the area E as an image to bedisplayed on the image display device 6 based on the acquired image 14and area information indicating the area E. Thus, when the line of sightextends from the position of the driver 10, the image of the area E isdisplayed on the image display device 6.

Thereafter, when the driver 10 shifts the line-of-sight position as doesthe driver 10 a, the image calculator 8 analyzes information about theline-of-sight position of the driver 10 based on image data captured bythe in-vehicle camera 11 and calculates, as a required image area, thearea F based on a result of the analysis. The image acquirer 2 acquiresthe acquired image 14 containing the calculated area F from the capturedimage 15. The image generator 4 generates a display image of the area Fas an image to be displayed on the image display device 6 based on theacquired image 14 and area information indicating the area F. Thus, whenthe driver 10 shifts the line-of-sight position to the position of thedriver 10 a, the image of the area F is displayed on the image displaydevice 6.

FIG. 8 and FIG. 9 are diagrams describing another example of an imageposition and area that are responsive to motion of the driver in thevehicular image-display system 7 of the present embodiment. When thedriver 10 desires to see a subject indicated at a position G in FIG. 8and FIG. 9, the driver 10 typically takes an action I of shiftinghis/her line-of-sight position as does a driver 10 b as an action ofseeing rearward using the mirror. Accordingly, there will arise a desireto see the subject indicated at the position G in FIG. 8 and FIG. 9 bytaking the action I even when the captured image 15 captured by theimage capturing device 3 is used in place of the mirror.

In this case, an image of the area E defined by and with reference tothe position of the image of FIG. 8 is preferably displayed on the imagedisplay device 6 when the line of sight extends from the position of thedriver 10, while an image of an area H defined by and with reference tothe position of the image of FIG. 8 is preferably displayed on the imagedisplay device 6 when the line of sight extends from the position of thedriver 10 b. According to the vehicular image-display system 7 of thepresent embodiment, it is possible to cause the image of the area E tobe displayed on the image display device 6 when line of sight extendsfrom the position of the driver 10 but, when the driver 10 shiftshis/her line-of-sight position to the position of the driver 10 b, causethe image of the area H to be displayed on the image display device 6.

FIG. 10 and FIG. 11 are diagrams describing still another example of animage position and area that are responsive to motion of the driver inthe vehicular image-display system 7 of the present embodiment. When thedriver 10 desires to see the mirror indicated by the area E of FIG. 10from a closer position, the driver 10 illustrated in FIG. 11 typicallytakes an action K of shifting his/her line-of-sight position as does adriver 10 c. Accordingly, there will arise a desire to see the mirror ina close-up manner by taking the action K even when the captured image 15captured by the image capturing device 3 is used in place of the mirror.

In this case, an image of the area E defined by and with reference tothe position of the image of FIG. 10 is preferably displayed on theimage display device 6 when line of sight extends from the position ofthe driver 10, while an image of an area J defined by and with referenceto the position of the image of FIG. 10 is preferably displayed on theimage display device 6 when line of sight extends from the position ofthe driver 10c. According to the vehicular image-display system 7 of thepresent embodiment, it is possible to cause the image of the area E tobe displayed on the image display device 6 when line of sight extendsfrom the position of the driver 10 but, when the driver 10 shiftshis/her line-of-sight position to the position of the driver 10c, causethe image of the area J to be displayed on the image display device 6.

It will be important that the position and area of an image to bedisplayed on the image display device 6 are changed depending online-of-sight position of a driver in this manner when the capturedimage 15 captured by the image capturing device 3 is used in place of amirror.

According to an embodiment, it is possible to reduce transmissionvolume.

The above-described embodiments are illustrative and do not limit thepresent invention. Thus, numerous additional modifications andvariations are possible in light of the above teachings. For example, atleast one element of different illustrative and exemplary embodimentsherein may be combined with each other or substituted for each otherwithin the scope of this disclosure and appended claims. Further,features of components of the embodiments, such as the number, theposition, and the shape are not limited the embodiments and thus may bepreferably set. It is therefore to be understood that within the scopeof the appended claims, the disclosure of the present invention may bepracticed otherwise than as specifically described herein.

Each of the functions of the described embodiments may be implemented byone or more processing circuits or circuitry. Processing circuitryincludes a programmed processor, as a processor includes circuitry. Aprocessing circuit also includes devices such as an application specificintegrated circuit (ASIC), digital signal processor (DSP), fieldprogrammable gate array (FPGA) and conventional circuit componentsarranged to perform the recited functions.

What is claimed is:
 1. A vehicular image-display system, comprising: animaging device configured to capture an image of surroundings of avehicle; first processing circuitry configured to generate an displayimage that is smaller in area than the acquired image, the display imagebeing generated based on motion of a driver who is driving the vehicle;and an image display configured to display the generated display image.2. The vehicular image-display system according to claim 1, furthercomprising second processing circuitry configured to calculate an imageposition and an area of the display image, based on the motion of thedriver.
 3. The vehicular image-display system according to claim 2,wherein the second processing circuitry is included in the imagecapturing device.
 4. The vehicular image-display system according toclaim 2, wherein the second processing circuitry is included in thecontrol device
 5. The vehicular image-display system according to claim2, wherein when the image position and the area of the display image aredetermined not to fall within an area of the acquired image, the secondprocessing circuitry is further configured to calculate the imageposition and the area of the image to fall within an area of theacquired image.
 6. The vehicular image-display system according to claim2, wherein the second processing circuitry is configured to analyze aline-of-sight position of the driver, and calculate the image positionand the area of the display image device based on a result of analysisof the line-of-sight position.
 7. The vehicular image-display systemaccording to claim 1, wherein the imaging device is provided in thevehicle.